Yes. You can. I have a friend who added new backing plates and took his 27 (much less boat than the 30), down the coast from the Vancouver BC area to Panama and through the canal and back up to Florida. Catalinas are good solid boats. They lack some of the details that you would find on more expensive boats (less teak and hardwood inside), but they are capable little boats. I almost bought one in Seattle that had just returned from a few year trip to the Sea of Cortez and back via the water.

"under rated?" No, many folks think highly of the Catalinas--just not for cruising. I know many people who love their small Catalinas for what they are--an inexpensive boat that is great for the Wednesday night harbor races and great for weekend trips and mild coastal cruising. They are by no means built to withstand the rigors of long passages involving ocean crossing and someone who pushes one into real cruising service is likely to be disappointed as these boats won't hold up over time to the punishment of the long distance cruising environment. It's just not what they were built for.

One can easily get a better small cruising vessel for the same money as a Catalina. If one already owns a Catalina, I'd still suggest selling and getting into a different small boat designed for cruising. If someone hands you a Catalina 30 on a silver platter, fully outfitted for cruising with every bell and whistle...maybe...nah...just sell it--they're easy to sell since everyone knows what they are and they're a respectable boat--and take the money to find a real cruising boat.

We put 10k miles on our Catalina 38, Ca, to Mx to FP to Samoa. She survived a tsunami getting knocked off her stands and a hurricne. A C36 made the same trip we did.

I sailed from San Diego to Salinas Ecuador on a Catalina Capri 26. This boat, checked all through the rigging, with proper equipment for blue water sailing showed to be a very smooth and fast boat. In rough and with proper storm sails, the Capri is very stable and handy. I did a fine single hand sailing and definitely, the blue water sailing is not up to the boat but the sailor. A sailboat is made to float and to go. So, with the proper equipment for sailors safety, for comfortable sailing and the proper equipment for comfort (Cooking, food preservation, etc. ), whatever boat is good.
The Capri has a fine space inside and I found, the Catalina 30 is about the same just some bigger. What is important on the 26 Capri. Don't waste any space inside with an in-border. A 9.9 HP Yamaha will be enough even in storm (tested).

Now, the final words are always up to the sipper. Each skipper has his preferences....

Boats are like cars. Some are made for the city, some for the country, some for off-road and some for racing through the deserts of Africa. If you try to use a boat for a purpose it was not designed for, you may be courting trouble.

Ocean crossings are tough on both people and boats, and the boat needs to be made for the job. Adapting a day sailer may make it a better bet, but it will cost and, at the end of the day, it will still be a day sailer.

I love Catalinas, Hunters and Bennys. They make great boats for a variety of purposes including blue water voyaging, The human component must be top class for crossing oceans....but the human needs the backing of a top class boat, designed for the job.

__________________
"if at first you don't succeed....Redefine success"!

Frankly I don't remember how it all came about exactly. I vaguely remember talking to a customs officer on a phone. She was saying it wasn't necessary to call in each time. I perhaps missed her saying "if I got a visa". San Diego ticked me off. It really must have been all a misunderstanding. I told them the lady in Neah Bay said I didn't need to clear? It's all fuzzy. They called and no one could vouch my story. still have the $5000.00 notice to pay "artifact." And the sold called clearance papers I thought I needed to enter Mexico were never asked for in the end. And thank you Auzzie for the heads up on the eBay items.